CLUTCH 2331280 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the system only under the following conditions:
There is an active diagnostic code or an easily repeated diagnostic code that is associated with the engine speed/timing circuit.
You have been directed here from another procedure. The following background information is related to this procedure:The engine uses two engine speed/timing sensors. Both of the engine speed/timing sensors detect the reference for engine speed and timing from a unique pattern on the camshaft gear. The Engine Control Module (ECM) counts the time between pulses that is created by the sensor as the gear rotates in order to determine rpm. The ECM remembers the pattern of the pulses. The ECM uses the pattern of the pulses in order to determine the position of the crankshaft.When the timing has been established, the ECM triggers each injector in the correct firing order at the correct time.The actual timing and duration of each injection is based on engine rpm and on load. If the engine is running and the signal from one of the camshaft position sensors is lost, no noticeable change in engine performance will be noticed.The engine will start and the engine will run when only one sensor signal is present from either of the sensors. The loss of the signal from both of the sensors during engine operation will result in the termination of injection and the shutting down the engine by the ECM. The loss of the signal from both of the sensors during start-up will prevent the engine from starting.Both sensors are magnetic sensors. The two sensors are not interchangeable. Do not switch the positions of the sensors. The two sensors must be replaced as a pair. If the sensors are replaced, a timing calibration is not necessary for the engine. Timing calibration is only necessary after replacing an ECM that will not communicate.If a replacement of the ECM is required, the ECM parameters and the timing calibration can be transferred from the suspect ECM to the replacement ECM. Timing calibration will not be necessary. This feature requires the Caterpillar Electronic Technician (ET) and this feature is only possible if the existing ECM can communicate with Cat ET. Use the procedure "Copy Configuration - ECM Replacement" on Cat ET. Refer to Troubleshooting, "Programming Parameters" for more information.When the sensors are being installed, complete all of the following tasks:
Lubricate the O-ring with oil.
Ensure that the sensor has a face seal inside the connector body. If a seal is damaged or missing, replace the seal.
Ensure that the sensor is fully seated into the engine before tightening the bracket bolt.
Ensure that the connector is latched on both sides.
Ensure that the harness is properly secured, and ensure that the harness is attached to the harness clip.
Illustration 1 g00931977
Schematic for the speed/timing sensors
Illustration 2 g01151050
Pin locations on ECM connector
(P2-48) Primary engine speed/timing positive
(P2-49) Primary engine speed/timing negative
(P2-58) Secondary engine speed/timing positive
(P2-59) Secondary engine speed/timing negative Test Step 1. Check for Active Diagnostic Codes and Logged Diagnostic Codes
Connect Cat ET to the